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A YANG Data Model for Hardware Management
draft-ietf-netmod-entity-01

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 8348.
Authors Andy Bierman , Martin Björklund , Jie Dong , Dan Romascanu
Last updated 2016-10-31
Replaces draft-entitydt-netmod-entity
RFC stream Internet Engineering Task Force (IETF)
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Stream WG state WG Document
Document shepherd Lou Berger
IESG IESG state Became RFC 8348 (Proposed Standard)
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Send notices to "Lou Berger" <lberger@labn.net>
draft-ietf-netmod-entity-01
Network Working Group                                         A. Bierman
Internet-Draft                                                 YumaWorks
Intended status: Standards Track                            M. Bjorklund
Expires: May 4, 2017                                      Tail-f Systems
                                                                 J. Dong
                                                     Huawei Technologies
                                                            D. Romascanu
                                                        October 31, 2016

               A YANG Data Model for Hardware Management
                      draft-ietf-netmod-entity-01

Abstract

   This document defines a YANG data model for the management of
   hardware on a single server.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on May 4, 2017.

Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of

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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
       1.1.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . .   2
   2.  Objectives  . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Hardware Data Model . . . . . . . . . . . . . . . . . . . . .   3
     3.1.  The Components Lists  . . . . . . . . . . . . . . . . . .   5
   4.  Relationship to ENTITY-MIB  . . . . . . . . . . . . . . . . .   5
   5.  Relationship to ENTITY-SENSOR-MIB . . . . . . . . . . . . . .   6
   6.  Relationship to ENTITY-STATE-MIB  . . . . . . . . . . . . . .   6
   7.  Hardware YANG Module  . . . . . . . . . . . . . . . . . . . .   6
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  34
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  35
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  35
   11. Normative References  . . . . . . . . . . . . . . . . . . . .  35
   Appendix A.  Open Issues  . . . . . . . . . . . . . . . . . . . .  36
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  36

1.  Introduction

   This document defines a YANG [I-D.ietf-netmod-rfc6020bis] data model
   for the management of hardware on a single server.

   The data model includes configuration data and state data (status
   information and counters for the collection of statistics).

1.1.  Terminology

   The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14, [RFC2119].

1.1.1.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Abbreviations before data node names: "rw" means configuration
      data (read-write) and "ro" state data (read-only).

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   o  Symbols after data node names: "?" means an optional node, "!"
      means a presence container, and "*" denotes a list and leaf-list.

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

2.  Objectives

   This section describes some of the design objectives for the hardware
   model.

   o  There are many common properties used to identify hardware
      components, which need to be supported in the hardware data model.

   o  There are many important information and states about the
      components, which needs to be collected from the devices which
      support the hardware data model.

   o  The hardware data model SHOULD be suitable for new implementations
      to use as is.

   o  The hardware data model defined in this document can be
      implemented on a system that also implements ENTITY-MIB, thus the
      mapping between the hardware data model and ENTITY-MIB SHOULD be
      clear.

3.  Hardware Data Model

   This document defines the YANG module "ietf-hardware", which has the
   following structure:

   module: ietf-hardware
       +--ro hardware-state
       |  +--ro last-change?   yang:date-and-time
       |  +--ro component* [name]
       |     +--ro name              string
       |     +--ro class             identityref
       |     +--ro physical-index?   int32 {entity-mib}?
       |     +--ro description?      string
       |     +--ro contained-in*     -> ../../component/name
       |     +--ro contains-child*   -> ../../component/name
       |     +--ro parent-rel-pos?   int32
       |     +--ro hardware-rev?     string
       |     +--ro firmware-rev?     string
       |     +--ro software-rev?     string

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       |     +--ro serial-num?       string
       |     +--ro mfg-name?         string
       |     +--ro model-name?       string
       |     +--ro alias?            string
       |     +--ro asset-id?         string
       |     +--ro is-fru?           boolean
       |     +--ro mfg-date?         yang:date-and-time
       |     +--ro uri*              inet:uri
       |     +--ro uuid?             yang:uuid
       |     +--ro state {entity-state}?
       |     |  +--ro state-last-changed?   yang:date-and-time
       |     |  +--ro admin-state?          admin-state
       |     |  +--ro oper-state?           oper-state
       |     |  +--ro usage-state?          usage-state
       |     |  +--ro alarm-status?         alarm-status
       |     |  +--ro standby-status?       standby-status
       |     +--ro sensor-data {entity-sensor}?
       |        +--ro data-type?              sensor-data-type
       |        +--ro data-scale?             sensor-data-scale
       |        +--ro precision?              sensor-precision
       |        +--ro value?                  sensor-value
       |        +--ro oper-status?            sensor-status
       |        +--ro sensor-units-display?   string
       |        +--ro value-timestamp?        yang:date-and-time
       |        +--ro value-update-rate?      uint32
       +--rw hardware {hardware-config}?
          +--rw component* [name]
             +--rw name           string
             +--rw serial-num?    string
             +--rw alias?         string
             +--rw asset-id?      string
             +--rw uri*           inet:uri
             +--rw admin-state?   admin-state {entity-state}?

     notifications:
       +---n harwdare-state-change
       +---n hardware-state-oper-enabled {entity-state}?
       |  +--ro name?           -> /hardware-state/component/name
       |  +--ro admin-state?
       |  |       -> /hardware-state/component/state/admin-state
       |  +--ro alarm-status?
       |          -> /hardware-state/component/state/alarm-status
       +---n hardware-state-oper-disabled {entity-state}?
          +--ro name?           -> /hardware-state/component/name
          +--ro admin-state?
          |       -> /hardware-state/component/state/admin-state
          +--ro alarm-status?
                  -> /hardware-state/component/state/alarm-status

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3.1.  The Components Lists

   The data model for hardware presented in this document uses a flat
   list of components.  Each component in the list is identified by its
   name.  Furthermore, each component has a mandatory "class" leaf.

   The "iana-entity" module defines YANG identities for the hardware
   types in the IANA-maintained "IANA-ENTITY-MIB" registry.

   The "class" leaf is a YANG identity that describes the type of the
   hardware.  Vendors are encouraged to either directly use one of the
   common IANA-defined identities, or derive a more specific identity
   from one of them.

   There is one optional list of configured components ("/hardware/
   component"), and a separate list for the operational state of all
   components ("/hardware-state/component").

4.  Relationship to ENTITY-MIB

   If the device implements the ENTITY-MIB [RFC6933], each entry in the
   /hardware-state/component list is mapped to one EntPhysicalEntry.
   Objects that are writable in the MIB are mapped to nodes in the
   /hardware/component list.

   The "physical-index" leaf MUST contain the value of the corresponding
   entPhysicalEntry's entPhysicalIndex.

   The "class" leaf is mapped to both entPhysicalClass and
   entPhysicalVendorType.  If the value of the "class" leaf is an
   identity that is either derived from or is one of the identities in
   the "iana-entity" module, then entPhysicalClass contains the
   corresponding IANAPhysicalClass enumeration value.  Otherwise,
   entPhysicalClass contains the IANAPhysicalClass value "other(1)".
   Vendors are encouraged to define an identity (derived from an
   identity in "iana-entity" if possible) for each enterprise-specific
   registration identifier used for entPhysicalVendorType, and use that
   identity for the "class" leaf.

   The following tables list the YANG data nodes with corresponding
   objects in the ENTITY-MIB.

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   +----------------------------------+--------------------------------+
   | YANG data node in /hardware-     | ENTITY-MIB object              |
   | state/component                  |                                |
   +----------------------------------+--------------------------------+
   | name                             | entPhysicalName                |
   | class                            | entPhysicalClass               |
   |                                  | entPhysicalVendorType          |
   | physical-index                   | entPhysicalIndex               |
   | description                      | entPhysicalDescr               |
   | contained-in                     | entPhysicalContainedIn         |
   | contains-child                   | entPhysicalChildIndex          |
   | parent-rel-pos                   | entPhysicalParentRelPos        |
   | hardware-rev                     | entPhysicalHardwareRev         |
   | firmware-rev                     | entPhysicalFirmwareRev         |
   | software-rev                     | entPhysicalSoftwareRev         |
   | serial-num                       | entPhysicalSerialNum           |
   | mfg-name                         | entPhysicalMfgName             |
   | model-name                       | entPhysicalModelName           |
   | alias                            | entPhysicalAlias               |
   | asset-id                         | entPhysicalAssetID             |
   | is-fru                           | entPhysicalIsFRU               |
   | mfg-date                         | entPhysicalMfgDate             |
   | uri                              | entPhysicalUris                |
   | uuid                             | entPhysicalUUID                |
   +----------------------------------+--------------------------------+

              YANG data nodes and related ENTITY-MIB objects

5.  Relationship to ENTITY-SENSOR-MIB

   TBD relationship to [RFC3433].

6.  Relationship to ENTITY-STATE-MIB

   TBD relationship to [RFC4268].

7.  Hardware YANG Module

   <CODE BEGINS> file "ietf-hardware@2016-10-25.yang"

   module ietf-hardware {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-hardware";
     prefix hw;

     import ietf-inet-types {
       prefix inet;
     }

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     import ietf-yang-types {
       prefix yang;
     }
     import iana-entity {
       prefix ianaent;
     }

     organization
       "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

     contact
       "WG Web:   <http://tools.ietf.org/wg/netmod/>
        WG List:  <mailto:netmod@ietf.org>

        WG Chair: Lou Berger
                  <mailto:lberger@labn.net>

        WG Chair: Kent Watsen
                  <mailto:kwatsen@juniper.net>

        Editor:   Andy Bierman
                  <mailto:andy@yumaworks.com>

        Editor:   Martin Bjorklund
                  <mailto:mbj@tail-f.com>

        Editor:   Jie Dong
                  <mailto:jie.dong@huawei.com>

        Editor:   Dan Romascanu
                  <mailto:dromasca@gmail.com>";

     // RFC Ed.: replace XXXX with actual RFC number and remove this
     // note.

     description
       "This module contains a collection of YANG definitions for
        managing hardware.

        Copyright (c) 2016 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject
        to the license terms contained in, the Simplified BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (http://trustee.ietf.org/license-info).

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        This version of this YANG module is part of RFC XXXX; see
        the RFC itself for full legal notices.";

     // RFC Ed.: update the date below with the date of RFC publication
     // and remove this note.
     revision 2016-10-25 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for Hardware Management";
     }

     /*
      * Features
      */

     feature entity-mib {
       description
         "This feature indicates that the device implements
          the ENTITY-MIB.";
       reference "RFC 6933: Entity MIB (Version 4)";
     }

     feature hardware-config {
       description
         "Indicates that the server supports configuration of
          hardware components.";
     }

     feature entity-state {
       description
         "Indicates the ENTITY-STATE-MIB objects are supported";
       reference "RFC 4268: Entity State MIB";
     }

     feature entity-sensor {
       description
         "Indicates the ENTITY-SENSOR-MIB objects are supported";
       reference "RFC 3433: Entity Sensor MIB";
     }

     /*
      * Typedefs
      */

     typedef admin-state {
       type enumeration {
         enum unknown {

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           value 1;
           description
             "The resource is unable to report administrative state.";
         }
         enum locked {
           value 2;
           description
             "The resource is administratively prohibited from use.";
         }
         enum shutting-down {
           value 3;
           description
             "The resource usage is administratively limited to current
              instances of use.";
         }
         enum unlocked {
           value 4;
           description
             "The resource is not administratively prohibited from
              use.";
         }
       }
       description
         "Represents the various possible administrative states.";
       reference "RFC 4268: EntityAdminState";
     }

     typedef oper-state {
       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report operational state.";
         }
         enum disabled {
           value 2;
           description
             "The resource is totally inoperable.";
         }
         enum enabled {
           value 3;
           description
             "The resource is partially or fully operable.";
         }
         enum testing {
           value 4;
           description
             "The resource is currently being tested and cannot

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              therefore report whether it is operational or not.";
         }
       }
       description
         "Represents the possible values of operational states.";
       reference "RFC 4268: EntityOperState";
     }

     typedef usage-state {
       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report usage state.";
         }
         enum idle {
           value 2;
           description
             "The resource is servicing no users.";
         }
         enum active {
           value 3;
           description
             "The resource is currently in use and it has sufficient
              spare capacity to provide for additional users.";
         }
         enum busy {
           value 4;
           description
             "The resource is currently in use, but it currently has
              no spare capacity to provide for additional users.";
         }
       }
       description
         "Represents the possible values of usage states.";
       reference "RFC 4268, EntityUsageState";
     }

     typedef alarm-status {
       type bits {
         bit unknown {
           position 0;
           description
             "The resource is unable to report alarm state.";
         }
         bit under-repair {
           position 1;
           description

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             "The resource is currently being repaired, which, depending
              on the implementation, may make the other values in this
              bit string not meaningful.";
         }
         bit critical {
           position 2;
           description
             "One or more critical alarms are active against the
              resource.";
         }
         bit major {
           position 3;
           description
             "One or more major alarms are active against the
              resource.";
         }
         bit minor {
           position 4;
           description
             "One or more minor alarms are active against the
              resource.";
         }
         bit warning {
           position 5;
           description
             "One or more warning alarms are active against the
              resource. This alarm status is not defined in X.733.";
         }
         bit indeterminate {
           position 6;
           description
             "One or more alarms of whose perceived severity cannot be
              determined are active against this resource.
              This alarm status is not defined in X.733.";
         }
       }
       description
         "Represents the possible values of alarm status.
          An Alarm [RFC3877] is a persistent indication of an error or
          warning condition.

          When no bits of this attribute are set, then no active
          alarms are known against this component and it is not under
          repair.";
       reference "RFC 4268: EntityAlarmStatus";
     }

     typedef standby-status {

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       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report standby state.";
         }
         enum hot-standby {
           value 2;
           description
             "The resource is not providing service, but it will be
              immediately able to take over the role of the resource
              to be backed up, without the need for initialization
              activity, and will contain the same information as the
              resource to be backed up.";
         }
         enum cold-standby {
           value 3;
           description
             "The resource is to back up another resource, but will not
              be immediately able to take over the role of a resource
              to be backed up, and will require some initialization
              activity.";
         }
         enum providing-service {
           value 4;
           description
             "The resource is providing service.";
         }
       }
       description
         "Represents the possible values of standby status.";
       reference "RFC 4268: EntityStandbyStatus";
     }

     typedef sensor-data-type {
       type enumeration {
         enum other {
           value 1;
           description
             "A measure other than those listed below.";
         }
         enum unknown {
           value 2;
           description
             "An unknown measurement, or arbitrary, relative numbers";
         }
         enum volts-AC {
           value 3;

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           description
             "A measure of electric potential (alternating current).";
         }
         enum volts-DC {
           value 4;
           description
             "A measure of electric potential (direct current).";
         }
         enum amperes {
           value 5;
           description
             "A measure of electric current.";
         }
         enum watts {
           value 6;
           description
             "A measure of power.";
         }
         enum hertz {
           value 7;
           description
             "A measure of frequency.";
         }
         enum celsius {
           value 8;
           description
             "A measure of temperature.";
         }
         enum percent-RH {
           value 9;
           description
             "A measure of percent relative humidity.";
         }
         enum rpm {
           value 10;
           description
             "A measure of shaft revolutions per minute.";
         }
         enum cmm {
           value 11;
           description
             "A measure of cubic meters per minute (airflow).";
         }
         enum truth-value {
           value 12;
           description
             "Value is one of 1 (true) or 2 (false)";
         }

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       }
       description
         "An node using this data type represents the Entity Sensor
          measurement data type associated with a physical sensor
          value. The actual data units are determined by examining an
          node of this type together with the associated
          sensor-data-scale node.

          An node of this type SHOULD be defined together with nodes
          of type sensor-data-scale and
          sensor-precision. These three types are used to
          identify the semantics of an node of type
          sensor-value.";
       reference "RFC 3433: EntitySensorDataType";
     }

     typedef sensor-data-scale {
       type enumeration {
         enum yocto {
           value 1;
           description
             "Data scaling factor of 10^-24.";
         }
         enum zepto {
           value 2;
           description
             "Data scaling factor of 10^-21.";
         }
         enum atto {
           value 3;
           description
             "Data scaling factor of 10^-18.";
         }
         enum femto {
           value 4;
           description
             "Data scaling factor of 10^-15.";
         }
         enum pico {
           value 5;
           description
             "Data scaling factor of 10^-12.";
         }
         enum nano {
           value 6;
           description
             "Data scaling factor of 10^-9.";
         }

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         enum micro {
           value 7;
           description
             "Data scaling factor of 10^-6.";
         }
         enum milli {
           value 8;
           description
             "Data scaling factor of 10^-3.";
         }
         enum units {
           value 9;
           description
             "Data scaling factor of 10^0.";
         }
         enum kilo {
           value 10;
           description
             "Data scaling factor of 10^3.";
         }
         enum mega {
           value 11;
           description
             "Data scaling factor of 10^6.";
         }
         enum giga {
           value 12;
           description
             "Data scaling factor of 10^9.";
         }
         enum tera {
           value 13;
           description
             "Data scaling factor of 10^12.";
         }
         enum exa {
           value 14;
           description
             "Data scaling factor of 10^15.";
         }
         enum peta {
           value 15;
           description
             "Data scaling factor of 10^18.";
         }
         enum zetta {
           value 16;
           description

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             "Data scaling factor of 10^21.";
         }
         enum yotta {
           value 17;
           description
             "Data scaling factor of 10^24.";
         }
       }
       description
         "An node using this data type represents a data scaling
          factor, represented with an International System of Units (SI)
          prefix.  The actual data units are determined by examining an
          node of this type together with the associated
          sensor-data-type.

          An node of this type SHOULD be defined together with nodes
          of type sensor-data-type and sensor-precision.
          Together, associated nodes of these three types are used to
          identify the semantics of an node of type
          sensor-value.";
       reference "RFC 3433: EntitySensorDataScale";
     }

     typedef sensor-precision {
       type int32 {
         range "-8 .. 9";
       }
       description
         "An node using this data type represents a sensor
          precision range.

          An node of this type SHOULD be defined together with nodes
          of type sensor-data-type and sensor-data-scale.
          Together, associated nodes of these three types are used to
          identify the semantics of an node of type
          sensor-value.

          If an node of this type contains a value in the range 1 to 9,
          it represents the number of decimal places in the fractional
          part of an associated sensor-value fixed- point number.

          If an node of this type contains a value in the range -8 to
          -1, it represents the number of accurate digits in the
          associated sensor-value fixed-point number.

          The value zero indicates the associated sensor-value
          node is not a fixed-point number.

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          Server implementors must choose a value for the associated
          sensor-precision node so that the precision and
          accuracy of the associated sensor-value node is
          correctly indicated.

          For example, a component representing a temperature
          sensor that can measure 0 degrees to 100 degrees C in 0.1
          degree increments, +/- 0.05 degrees, would have an
          sensor-precision value of '1', an
          sensor-data-scale value of 'units', and an
          sensor-value ranging from '0' to '1000'.  The
          sensor-value would be interpreted as
          'degrees C * 10'.";
       reference "RFC 3433: EntitySensorPrecision";
     }

     typedef sensor-value {
       type int32 {
         range "-1000000000 .. 1000000000";
       }
       description
        "An node using this data type represents an Entity Sensor
         value.

         An node of this type SHOULD be defined together with nodes
         of type sensor-data-type, sensor-data-scale, and
         sensor-precision.  Together, associated nodes of those
         three types are used to identify the semantics of an node of
         this data type.

         The semantics of an node using this data type are determined
         by the value of the associated sensor-data-type node.

         If the associated sensor-data-type node is equal to
         'voltsAC', 'voltsDC', 'amperes', 'watts', 'hertz',
         'celsius', or 'cmm', then an node of this type MUST
         contain a fixed point number ranging from -999,999,999 to
         +999,999,999.  The value -1000000000 indicates an underflow
         error. The value +1000000000 indicates an overflow error.  The
         sensor-precision indicates how many fractional digits
         are represented in the associated sensor-value node.

         If the associated sensor-data-type node is equal to
         'percentRH', then an node of this type MUST contain a
         number ranging from 0 to 100.

         If the associated sensor-data-type node is equal to
         'rpm', then an node of this type MUST contain a number

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         ranging from -999,999,999 to +999,999,999.

         If the associated sensor-data-type node is equal to
         'truthvalue', then an node of this type MUST contain
         either the value 1 (true) or the value 2 (false)'.

         If the associated sensor-data-type node is equal to
         'other' or unknown', then an node of this type MUST
         contain a number ranging from -1000000000 to 1000000000.";
       reference "RFC 3433: EntitySensorValue";
     }

     typedef sensor-status {
       type enumeration {
         enum ok {
           value 1;
           description
             "Indicates that the server can obtain the sensor value.";
         }
         enum unavailable {
           value 2;
           description
             "Indicates that the server presently cannot obtain the
              sensor value.";
         }
         enum nonoperational {
           value 3;
           description
             "Indicates that the server believes the sensor is broken.
              The sensor could have a hard failure (disconnected wire),
              or a soft failure such as out-of-range, jittery, or wildly
              fluctuating readings.";
         }
       }
       description
         "An node using this data type represents the operational
          status of a physical sensor.";
       reference "RFC 3433: EntitySensorStatus";
     }

     /*
      * Operational state data nodes
      */

     container hardware-state {
       config false;
       description
         "Data nodes for the operational state of components.";

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       leaf last-change {
         type yang:date-and-time;
         description
           "The time the '/hardware-state/component' list
            changed.";
       }

       list component {
         key name;
         description
           "List of components.";
         reference "RFC 6933: entPhysicalEntry";

         leaf name {
           type string;
           description
             "Administrative name assigned to this component.
              No restrictions apply. Not required to be the same as
              entPhysicalName.";
         }

         leaf class {
           type identityref {
             base ianaent:entity-physical-class;
           }
           mandatory true;
           description
             "An indication of the general hardware type
              of the component.";
           reference "RFC 6933: entPhysicalClass";
         }

         leaf physical-index {
           if-feature entity-mib;
           type int32 {
             range "1..2147483647";
           }
           description
             "The entPhysicalIndex for the entPhysicalEntry represented
              by this list entry.";
           reference "RFC 6933: entPhysicalIndex";
         }

         leaf description {
           type string;
           description
             "A textual description of component.  This node
              should contain a string that identifies the manufacturer's

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              name for the component and should be set to a
              distinct value for each version or model of the
              component.";
           reference "RFC 6933: entPhysicalDescr";
         }

         leaf-list contained-in {
           type leafref {
             path "../../component/name";
           }
           description
             "The name of the component that 'contains'
              this component.";
           reference "RFC 6933: entPhysicalContainedIn";
         }

         leaf-list contains-child {
           type leafref {
             path "../../component/name";
           }
           description
             "The name of the contained component.";
           reference "RFC 6933: entPhysicalChildIndex";
         }

         leaf parent-rel-pos {
           type int32 {
             range "0 .. 2147483647";
           }
           description
             "An indication of the relative position of this child
              component among all its sibling components.  Sibling
              components are defined as components that share the
              same instance values of each of the contained-in
              and class elements.";
           reference "RFC 6933: entPhysicalParentRelPos";
         }

         leaf hardware-rev {
           type string;
           description
             "The vendor-specific hardware revision string for the
              component.  The preferred value is the hardware
              revision identifier actually printed on the component
              itself (if present).";
           reference "RFC 6933: entPhysicalHardwareRev";
         }

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         leaf firmware-rev {
           type string;
           description
             "The vendor-specific firmware revision string for the
              component.";
           reference "RFC 6933: entPhysicalFirmwareRev";
         }

         leaf software-rev {
           type string;
           description
             "The vendor-specific software revision string for the
              component.";
           reference "RFC 6933: entPhysicalSoftwareRev";
         }

         leaf serial-num {
           type string;
           description
             "The vendor-specific serial number string for the
              component.  The preferred value is the serial number
              string actually printed on the component itself (if
              present).

              If a serial number has been configured for this component
              in /hardware/component/serial-num, this node contains
              the configured value.";
           reference "RFC 6933: entPhysicalSerialNum";
         }

         leaf mfg-name {
           type string;
           description
             "The name of the manufacturer of this physical component.
              The preferred value is the manufacturer name string
              actually printed on the component itself (if present).

              Note that comparisons between instances of the model-name,
              firmware-rev, software-rev, and the serial-num nodes are
              only meaningful amongst component with the same
              value of mfg-name.

              If the manufacturer name string associated with the
              physical component is unknown to the server, then this
              node will contain a zero-length string.";
           reference "RFC 6933: entPhysicalMfgName";
         }

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         leaf model-name {
           type string;
           description
             "The vendor-specific model name identifier string
              associated with this physical component.  The preferred
              value is the customer-visible part number, which may be
              printed on the component itself.

              If the model name string associated with the physical
              component is unknown to the server, then this node will
              contain a zero-length string.";
           reference "RFC 6933: entPhysicalModelName";
         }

         leaf alias {
           type string {
             length "0 .. 32";
           }
           description
             "An 'alias' name for the component, as specified by
              a network manager, and provides a non-volatile 'handle'
              for the component.

              If an alias has been configured for this component in
              /hardware/component/alias, this node contains the
              configured value.  If no such alias has been configured,
              the server may set the value of this node to a locally
              unique value.";
           reference "RFC 6933: entPhysicalAlias";
         }

         leaf asset-id {
           type string {
             length "0 .. 32";
           }
           description
             "This node is a user-assigned asset tracking identifier
              (as specified by a network manager) for the component
              and provides non-volatile storage of this information.

              If an asset tracking identifier has been configured for
              this component in /hardware/component/addet-id, this
              node contains the configured value.";
           reference "RFC 6933: entPhysicalAssetID";
         }

         leaf is-fru {
           type boolean;

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           description
             "This node indicates whether or not this component
              is considered a 'field replaceable unit' by the vendor.
              If this node contains the value 'true', then this
              component identifies a field replaceable unit.  For all
              components that are permanently contained within a field
              replaceable unit, the value 'false' should be returned
              for this node.";
           reference "RFC 6933: entPhysicalIsFRU";
         }

         leaf mfg-date {
           type yang:date-and-time;
           description
             "The date of manufacturing of the managed component.";
           reference "RFC 6933: entPhysicalMfgDate";
         }

         leaf-list uri {
           type inet:uri;
           description
             "This node contains identification information about the
              component.

              If uris have been configured for this component in
              /hardware/component/uri, this node contains the
              configured values.";
           reference "RFC 6933: entPhysicalUris";
         }

         leaf uuid {
           type yang:uuid;
           description
             "A Universally Unique Identifier of the component.";
           reference "RFC 6933: entPhysicalUUID";
         }

         container state {
           if-feature entity-state;
           description
             "State-related nodes";
           reference "RFC 4268: Entity State MIB";

           leaf state-last-changed {
             type yang:date-and-time;
             description
               "The date and time when the value of any of the
                admin-state, oper-state, usage-state, alarm-status, or

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                standby-status changed for this component.

                If there has been no change since the last
                re-initialization of the local system, this node
                contains the date and time of local system
                initialization.  If there has been no change since the
                component was added to the local system, this node
                contains the date and time of the insertion.";
             reference "RFC 4268: entStateLastChanged";
           }

           leaf admin-state {
             type admin-state;
             description
               "The administrative state for this component.

                This node refers to an entities administrative
                permission to service both other entities within its
                containment hierarchy as well other users of its
                services defined by means outside the scope of this
                module.

                Some components exhibit only a subset of the
                remaining administrative state values.  Some entities
                cannot be locked, and hence this node exhibits only the
                'unlocked' state.  Other entities cannot be shutdown
                gracefully, and hence this node does not exhibit the
                'shutting-down' state.";
             reference "RFC 4268: entStateAdmin";
           }

           leaf oper-state {
             type oper-state;
             description
               "The operational state for this component.

                Note that this node does not follow the administrative
                state.  An administrative state of down does not predict
                an operational state of disabled.

                Note that some implementations may not be able to
                accurately report oper-state while the admin-state node
                has a value other than 'unlocked'.  In these cases, this
                node MUST have a value of 'unknown'.";
             reference "RFC 4268: entStateOper";
           }

           leaf usage-state {

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             type usage-state;
             description
               "The usage state for this component.

                This node refers to a component's ability to service
                more components in a containment hierarchy.

                Some entities will exhibit only a subset of the usage
                state values.  Entities that are unable to ever service
                any entities within a containment hierarchy will always
                have a usage state of 'busy'.  Some entities will only
                ever be able to support one component within its
                containment hierarchy and will therefore only exhibit
                values of 'idle' and 'busy'.";
             reference "RFC 4268, entStateUsage";
           }

           leaf alarm-status {
             type alarm-status;
             description
               "The alarm status for this component.  It does not
                include the alarms raised on child components within its
                containment hierarchy.";
             reference "RFC 4268: entStateAlarm";
           }

           leaf standby-status {
             type standby-status;
             description
               "The standby status for this component.

                Some entities will exhibit only a subset of the
                remaining standby state values.  If this component
                cannot operate in a standby role, the value of this
                node will always be 'providing-service'.";
             reference "RFC 4268: entStateStandby";
           }
         }

         container sensor-data {
           when 'derived-from-or-self(../class,
                                      "ianaent:sensor")' {
             description
               "Sensor data nodes present for any component of type
                'sensor'";
           }
           if-feature entity-sensor;
           description

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             "Sensor-related nodes.";
           reference "RFC 3433: Entity Sensor MIB";

           leaf data-type {
             type sensor-data-type;
             description
               "The type of data units associated with the
                sensor value";
             reference "RFC 3433: entPhySensorType";
           }

           leaf data-scale {
             type sensor-data-scale;
             description
               "The (power of 10) scaling factor associated
                with the sensor value";
             reference "RFC 3433: entPhySensorScale";
           }

           leaf precision {
             type sensor-precision;
             description
               "The number of decimal places of precision
                associated with the sensor value";
             reference "RFC 3433: entPhySensorPrecision";
           }

           leaf value {
             type sensor-value;
             description
               "The most recent measurement obtained by the server
                for this sensor.";
             reference "RFC 3433: entPhySensorValue";
           }

           leaf oper-status {
             type sensor-status;
             description
               "The operational status of the sensor.";
             reference "RFC 3433: entPhySensorOperStatus";
           }

           leaf sensor-units-display {
             type string;
             description
               "A textual description of the data units that should be
                used in the display of the sensor value.";
             reference "RFC 3433: entPhySensorUnitsDisplay";

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           }

           leaf value-timestamp {
             type yang:date-and-time;
             description
               "The time the status and/or value of this sensor was
                last obtained by the server.";
             reference "RFC 3433: entPhySensorValueTimeStamp";
           }

           leaf value-update-rate {
             type uint32;
             units "milliseconds";
             description
               "An indication of the frequency that the server updates
                the associated 'value' node, representing in
                milliseconds.  The value zero indicates:

                 - the sensor value is updated on demand (e.g.,
                   when polled by the server for a get-request),
                 - the sensor value is updated when the sensor
                   value changes (event-driven),
                 - the server does not know the update rate.";
             reference "RFC 3433: entPhySensorValueUpdateRate";
           }
         }
       }
     }

     /*
      * Configuration data nodes
      */

     container hardware {
       if-feature hardware-config;
       description
         "Configuration parameters for components.";

       list component {
         key name;
         description
           "List of configuration data for components.";

         leaf name {
           type string;
           description
             "Administrative name assigned to this component.
              No restrictions apply.";

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         }

         leaf serial-num {
           type string;
           description
             "The vendor-specific serial number string for the
              component.  The preferred value is the serial number
              string actually printed on the component itself (if
              present).

              This node is indented to be used for components
              for which the server cannot determine the serial number.";
           reference "RFC 6933: entPhysicalSerialNum";
         }

         leaf alias {
           type string {
             length "0 .. 32";
           }
           description
             "This node is an 'alias' name for the component, as
              specified by a network manager, and provides a non-
              volatile 'handle' for the component.";
           reference "RFC 6933: entPhysicalAlias";
         }

         leaf asset-id {
           type string {
             length "0 .. 32";
           }
           description
             "This node is a user-assigned asset tracking identifier
              (as specified by a network manager) for the component";
           reference "RFC 6933: entPhysicalAssetID";
         }

         leaf-list uri {
           type inet:uri;
           description
             "This node contains identification information about the
              component.";
           reference "RFC 6933: entPhysicalUris";
         }

         leaf admin-state {
           if-feature entity-state;
           type admin-state;
           description

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             "The administrative state for this component.

              This node refers to a component's administrative
              permission to service both other entities within
              its containment hierarchy as well other users of
              its services defined by means outside the scope
              of this module.

              Some components exhibit only a subset of the
              remaining administrative state values.  Some entities
              cannot be locked, and hence this node exhibits only
              the 'unlocked' state.  Other entities cannot be shutdown
              gracefully, and hence this node does not exhibit the
              'shutting-down' state.";
           reference "RFC 4268, entStateAdmin";
         }
       }
     }

     /*
      * Notifications
      */

     notification harwdare-state-change {
       description
         "A hardware-state-change notification is generated when the
          value of /hardware-state/last-change changes.";
       reference "RFC 6933, entConfigChange";
     }

     notification hardware-state-oper-enabled {
       if-feature entity-state;
       description
         "A hardware-state-oper-enabled notification signifies that
          a component has transitioned into the 'enabled' state.";

       leaf name {
         type leafref {
           path "/hardware-state/component/name";
         }
         description
           "The name of the component that has transitioned into the
            'enabled' state.";
       }
       leaf admin-state {
         type leafref {
           path "/hardware-state/component/state/admin-state";
         }

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         description
           "The administrative state for the component.";
       }
       leaf alarm-status {
         type leafref {
           path "/hardware-state/component/state/alarm-status";
         }
         description
           "The alarm status for the component.";
       }
       reference "RFC 4268, entStateOperEnabled";
     }

     notification hardware-state-oper-disabled {
       if-feature entity-state;
       description
         "A hardware-state-oper-disabled notification signifies that
          a component has transitioned into the 'disabled' state.";

       leaf name {
         type leafref {
           path "/hardware-state/component/name";
         }
         description
           "The name of the component that has transitioned into the
            'disabled' state.";
       }
       leaf admin-state {
         type leafref {
           path "/hardware-state/component/state/admin-state";
         }
         description
           "The administrative state for the component.";
       }
       leaf alarm-status {
         type leafref {
           path "/hardware-state/component/state/alarm-status";
         }
         description
           "The alarm status for the component.";
       }
       reference "RFC 4268, entStateOperDisabled";
     }

   }

   <CODE ENDS>

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   <CODE BEGINS> file "iana-entity@2016-10-25.yang"

   module iana-entity {
     namespace "urn:ietf:params:xml:ns:yang:iana-entity";
     prefix ianaent;

     organization "IANA";
     contact
       "        Internet Assigned Numbers Authority

        Postal: ICANN
                4676 Admiralty Way, Suite 330
                Marina del Rey, CA 90292

        Tel:    +1 310 823 9358
        <mailto:iana@iana.org>";

     description
       "IANA defined identities for physical class.";
     reference
       "https://www.iana.org/assignments/ianaentity-mib/ianaentity-mib";

     // RFC Ed.: replace XXXX with actual RFC number and remove this
     // note.

     // RFC Ed.: update the date below with the date of RFC publication
     // and remove this note.
     revision 2016-10-25 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for hardware Management";
     }

     /*
      * Identities
      */

     identity entity-physical-class {
       description
         "This identity is the base for all physical entity class
          identifiers.";
     }

     identity unknown {
       base ianaent:entity-physical-class;

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       description
         "This identity is applicable if the physical entity class
          is unknown to the server.";
     }

     identity chassis {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is an overall container for networking equipment.  Any class
          of physical entity, except a stack, may be contained within a
          chassis; a chassis may only be contained within a stack.";
     }

     identity backplane {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of device for aggregating and forwarding
          networking traffic, such as a shared backplane in a modular
          ethernet switch.  Note that an implementation may model a
          backplane as a single physical entity, which is actually
          implemented as multiple discrete physical components (within a
          chassis or stack).";
     }

     identity container {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is capable of containing one or more removable physical
          entities, possibly of different types.  For example, each
          (empty or full) slot in a chassis will be modeled as a
          container.  Note that all removable physical entities should
          be modeled within a container entity, such as field-
          replaceable modules, fans, or power supplies.  Note that all
          known containers should be modeled by the agent, including
          empty containers.";
     }

     identity power-supply {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is a power-supplying component.";
     }

     identity fan {

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       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is a fan or other heat-reduction component.";
     }

     identity sensor {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of sensor, such as a temperature sensor within a
          router chassis.";
     }

     identity module {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of self-contained sub-system.  If a 'module'
          entity is removable, then it should be modeled within a
          container entity; otherwise, it should be modeled directly
          within another physical entity (e.g., a chassis or another
          module).";
     }

     identity port {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of networking port, capable of receiving and/or
          transmitting networking traffic.";
     }

     identity stack {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of super-container (possibly virtual) intended to
          group together multiple chassis entities.  A stack may be
          realized by a 'virtual' cable, a real interconnect cable
          attached to multiple chassis, or multiple interconnect cables.
          A stack should not be modeled within any other physical
          entities, but a stack may be contained within another stack.
          Only chassis entities should be contained within a stack.";
     }

     identity cpu {
       base ianaent:entity-physical-class;

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       description
         "This identity is applicable if the physical entity class
          is some sort of central processing unit.";
     }

     identity energy-object {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of energy object, i.e., a piece of equipment that
          is part of or attached to a communications network that is
          monitored, controlled, or aids in the management of another
          device for Energy Management.";
     }

     identity battery {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of battery.";
     }

     identity storage-drive {
       base ianaent:entity-physical-class;
       description
         "This identity is applicable if the physical entity class
          is some sort of entity with data storage capability as main
          functionality, e.g., disk drive (HDD), solid state device
          (SSD), hybrid (SSHD), object storage (OSD) or other.";
     }
   }

   <CODE ENDS>

8.  IANA Considerations

   This document registers a URI in the IETF XML registry [RFC3688].
   Following the format in RFC 3688, the following registration is
   requested to be made.

        URI: urn:ietf:params:xml:ns:yang:ietf-hardware

        Registrant Contact: The IESG.

        XML: N/A, the requested URI is an XML namespace.

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   This document registers a YANG module in the YANG Module Names
   registry [RFC6020].

     name:         ietf-hardware
     namespace:    urn:ietf:params:xml:ns:yang:ietf-hardware
     prefix:       hw
     reference:    RFC XXXX

9.  Security Considerations

   TBD

10.  Acknowledgements

   TBD

11.  Normative References

   [I-D.ietf-netmod-rfc6020bis]
              Bjorklund, M., "The YANG 1.1 Data Modeling Language",
              draft-ietf-netmod-rfc6020bis-14 (work in progress), June
              2016.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC3433]  Bierman, A., Romascanu, D., and K. Norseth, "Entity Sensor
              Management Information Base", RFC 3433,
              DOI 10.17487/RFC3433, December 2002,
              <http://www.rfc-editor.org/info/rfc3433>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <http://www.rfc-editor.org/info/rfc3688>.

   [RFC4268]  Chisholm, S. and D. Perkins, "Entity State MIB", RFC 4268,
              DOI 10.17487/RFC4268, November 2005,
              <http://www.rfc-editor.org/info/rfc4268>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <http://www.rfc-editor.org/info/rfc6020>.

Bierman, et al.            Expires May 4, 2017                 [Page 35]
Internet-Draft           YANG Entity Management             October 2016

   [RFC6933]  Bierman, A., Romascanu, D., Quittek, J., and M.
              Chandramouli, "Entity MIB (Version 4)", RFC 6933,
              DOI 10.17487/RFC6933, May 2013,
              <http://www.rfc-editor.org/info/rfc6933>.

Appendix A.  Open Issues

   o  Should the model support pre-configuration of hardware components?
      The current model supports pre-configuration of components
      provided the operator knows the name of the component to be
      installed.  A more useful model would use the parent component,
      class, and parent-rel-pos as identification.  If the system
      detects a component and there is configuration available for the
      parent component, class, and parent-rel-pos then the system would
      instatiate the component with the provided name, and optionally
      additional parameters.

   o  Is there a need for a standard action 'reset' that can be used to
      reset components?

Authors' Addresses

   Andy Bierman
   YumaWorks

   Email: andy@yumaworks.com

   Martin Bjorklund
   Tail-f Systems

   Email: mbj@tail-f.com

   Jie Dong
   Huawei Technologies

   Email: jie.dong@huawei.com

   Dan Romascanu

   Email: dromasca@gmail.com

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